One of Australia's main airport terminals was shut down for eight hours yesterday as emergency crews hunted in vain for the cause of a mystery illness which struck down nearly 60 staff and passengers in the building, officials said.

Paramedics, firefighters and hazardous materials crews in full protective clothing rushed to Melbourne airport early Monday after staff in a domestic terminal began suffering nausea and vomiting, dizziness, headaches and shortness of breath.

Up to 2,000 staff, passengers and their friends were evacuated and the terminal shut down around 10:00 am while emergency crews tested air conditioning units and other facilities in an unsuccessful search for what was causing the illness.

Ambulance service spokesman James Howe said 47 people were taken to hospital and another 10 were treated at the scene for the symptoms.